Beatrice of Brandenburg, was a German princess and a member of the House of Ascania in the Brandenburg branch. By her two marriages she was Duchess of Świdnica and Koźle-Bytom-Siewierz. She was the second daughter of Otto V the Long, Margrave of Brandenburg-Salzwedel, by his wife Judith of Henneberg, daughter of Count Herman I of Henneberg and heiress of Coburg and Schmalkalden.
Life
Family
Beatrice had six siblings, three brothers and three sisters. From her brothers, Albert and Otto died young and the eldest, Herman, inherited the whole paternal domains. Beatrice's young sister Matilda married in 1287/88 with Henry IV Probus, Duke of Wrocław and High Duke of Poland. The other two sisters are Kunigunde, who died unmarried, and Judith, married in 1303 with Rudolf I, Duke of Saxe-Wittenberg. It is probable that the wedding of Beatrice into the Silesian branch of the Piast dynasty was instrumental to Matilda's future wedding with Henry IV.
First Marriage
One of the first tasks of Bolko I the Strict as sole Duke of Świdnica was protect his modest inheritance from the growing power of Henry IV Probus, Duke of Wroclaw. To that end, he decided to enter in an alliance with the Margraves of Brandenburg, cemented with the betrothal between him and Beatrice, who took in the city ofSpandau on 19 April 1279; however, because of the close relationship between the groom and bride, the formal wedding was performed more than five years later, on 4 October 1284 in the city of Berlin. Together Bolko I and Beatrice had ten children:
Bolko I died suddenly on 9 November 1301, and was buried in Grüssau Abbey. At the time, Beatrice was heavily pregnant with their youngest daughter, Anna, who was born two weeks later. Bolko I was succeeded by his sons, but because they were minors at that time, Beatrice's brother Herman, Margrave of Brandenburg-Salzwedel assumed the regency of his domains and the guardianship of her children. The custody of Henry V the Fat's sons and the regency of his lands were taken by King Wenceslaus II of Bohemia. After almost seven years of widowhood, Beatrice remarried by 21 September 1308 to Władysław, Duke of Koźle-Bytom-Siewierz. They had two children: